1. Field of the Invention
The present invention relates to a rotary electric machine that includes a bus-bar unit.
2. Description of the Background Art
In conventional stators, which include coil windings, of rotary electric machines, there have been many cases in which the stators are connected, by bus-bar units respectively provided at one side of each of stator cores, to coils arranged in each of slots, whereby electrical circuits are configured. In the cases, there has been a stator in which a bus bar is arranged on a coil end of the stator in accordance with a limitation of an area in which the stator in a housing can be arranged (for example, refer to Patent Document 1).
[Patent Document 1]
Japanese Laid-Open Patent Publication No. 2012-143091
In conventional rotary electric machines, when a bus bar for connecting a coil is arranged on a coil end, a configuration area of a bus-bar unit composing the bus bar is narrow, and it is difficult that a sufficient insulation distance between the bus bar and the coil is maintained. Moreover, when large current is passed through the bus bar, a sufficient cross-sectional area must be maintained in accordance with a consideration for a permissive current density, and the bus-bar unit has a tendency in that the bus-bar unit is extended in an axis direction of each of the rotary electric machines. As a result, there has been a problem in that a whole height of the stator is increased, whereby a size of each of the rotary electric machines is increased.
In the conventional art described in Patent Document 1, a bus-bar module is configured by separating four bus bars to two-step bus bars. However, the bus-bar module has a two-step configuration, so that there has been a problem in that the bus-bar module, in which all bus bars are integrated, must be reformed after two bus bars are formed. Moreover, in order to realize a constant structure, there has been a problem in that a forming resin must have a predefined thickness, and an excess insulation distance is required. As a result, there has been a problem in that the whole height of the stator is increased.